Acacia Density, Edaphic, and Climatic Factors Shape Plant Assemblages in Regrowth Montane Forests in Southeastern Australia

Round 1

Reviewer 1 Report

This paper explores the variability in tree density and climatic and edaphic factors on plant species diversity in montane regrowth forests in southern Australia. The results highlight the density of Acacia is a key biotic filter that influences the occurrence of many understorey plant species and shapes plant community turnover. This is very important to understand the regeneration of plant communities after harvesting. This manuscript is well written and has important implications to the forest management. I just have some specific suggestions listed below.

Title, I suggest give a clearer title to highlight your results that interests the readers.

Introduction

L40-43, why did the authors state the beta diversity here? As you did not calculate the difference among the sites.

L75-76, this sentence should add the research background like “after timber harvesting or in regrowth stands”, as you know, many studies related to regenerating tree species on the plant communities in natural forest, etc.

L83-87, the authors aimed to answer three questions, species density, edaphic and climate in shaping community composition, I suggest the authors to add another question that the relative contributions of density, edaphic and climate factors in shaping community composition by using variance partition analysis here.

Materials and Methods

L109-111, the authors should give more detail information about the clearfell, burn and sow silvicultural system. Did the authors consider these two methods differences, or consider them as a treatment or random factor for the analysis? Meanwhile, the authors discussed in the discussion part.

L157-159, which kind of transformation should give the specific method.

L164-166, the authors used the Pearson correlations > |0.6| to eliminate the collinearity, maybe the authors could use VIF to select the variables to conduct the analysis. In addition, the stepwise regression also suits for the variables selection here.

Results

Figure 2, I suggest change the box and whisker plot to Violin plot, this maybe give more information about the data distribution of your results here.

Figure 3, the authors used 90% credible intervals here, what is the main reason?

Figure 4, the authors did a vpa for each species, maybe the vpa for different age classes or sites is also very important and give more implication to the management.

Conclusions

L440-442, please give the explanation according to your results.

Author Response

Please find attached our response to both reviewers

thank you

Sabine

Author Response File: Author Response.docx

Reviewer 2 Report

Review of " Multiple factors shape plant assemblages in regrowth montane for-2 ests in southeastern Australia " by Singh et al. submitted to Forest.

 

This paper analyses the effects of stand age, environmental abiotic factors and the cover of two dominant species on species composition in the regenerating communities in several logged Eucalyptus forests in Southern Australia.

In general the paper is well written. There are however some points that need clarification (see bellow), justification or even been removed from the main text (see comment about L251-260 and Figure 4). Also, I miss a justification or explanation of not including "age" (of the stand) as a factor in the models fitted.

 

Minor comments.

L26-27: The "environmental tolerance" is not the "locations" but the range of environmental conditions where a species can growth. In fact the fundamental (or realized) niche is not a set of locations but the portion of the hyper dimensional environmental space where the combination of conditions allow the species growth.

L30-45: This digression about species interactions and beta diversity is very interesting but as the study does not measure neither of them, it could be removed.

L87: You did not measure beta diversity. You may remove this.

L110: Please, include a reference for this sylvicultural system.

L162- Why you don't include "age" as a factor  in mvabund and boral analyses (and maybe its interactions with some of the other continuous predictors) ? Justify in methods and comment in the discussion what could have been the effects of its inclusion.

L177: "measured unobserved environmental predictors" If they are unobserved they cannot be measured. Please, revise this.

L181: I think that this ability to assess species interactions is one of the strengths of GLLVM. However you did not present results nor discuss anything about these in the paper. Therefore you may remove this analysis at all.

L213: Total Nitrogen was not significantly different between in 5-7 years and the oldest stands (see Fig. 2).

L251-260 (and Fig. 4): Could the latent variables explain a certain percentage of the variance? Could they be considered in variance partitioning? If they couldn’t, and if you don’t consider important the effects of biotic interactions (L181-182)  I cannot see the need for GVLLM in addition to the joint analysis with mvabund.

L293-296: This may be explicitly tested including the interaction between Acacia cover and the abiotic factors.

L338: "contrasting responses to logging disturbance"

L353: "provided that moisture availability "

L367-368: "from large soil seed banks"

L420-428: I cannot see any result sustaining this affirmation that "wetter sites have higher diversity than drier sites" or that "aridity influenced the overall pattern of community composition". In fact I cannot see from which analyses could these result come from. Note also that "diversity" is not the same as "community composition". Did you remove or forget to include some analysis or some result (e.g., figure or table)?

L442: You have not measured or provided a meassure "turnover in species composition between sites", therefore, you cannot affirm if it is considerable or not.

L444-445: You have not included interactions between predictors in your models, therefore you should use other expression instead of "interaction of factors". Or recognize that the "complex patterns" *may be* the result of the interactions that you did not /could not assess.

Author Response

Please find attached our response to both reviewers,

thank you 

Sabine

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The authors improved the manuscript a  lot.  I do not have any other comments.